The present invention relates to a method and apparatus for wetting an advancing filament bundle which is capable of closely controlling the amount of the fluid applied to the bundle.
In the production of synthetic multifilament yarns or synthetic multifilament tows, it is known to apply a fluid to the filament bundle forming the yarn or tow for purposes of forming a yarn coherence, or enabling further processing, or effecting a cooling. In this process, the fluid may be applied by a nozzle, which generates a spray jet that is directed toward the filament bundle, as is disclosed, for example, in EP 0 344 649. Methods and apparatus of this type have been found satisfactory in particular for a continuous wetting of a filament bundle.
To wet a filament bundle at a varied speed of advance with different applications of fluid, nozzles of the described type are however suited only to a limited extent. For example, a reduction of the fluid quantity that is sprayed on by the nozzle, directly leads to a change in the spray pattern or spray angle. Thus, it is possible only to a limited extent to influence the fluid application to the filament bundle by controlling the nozzle. The known method and the known device are unable to perform a fine adjustment of the fluid applications to the filament bundle.
It is therefore an object of the invention to further develop a method of wetting an advancing filament bundle as well as a device of the described type for carrying out the method in such a manner that the filament bundle is able to receive at a speed of advance an adjustable and substantially constant application of fluid.